A subset of a topological group which is closed as a subset and also a subgroup.

# Closed Subgroup

## See also

Effective Action, Free Action, Group, Group Orbit, Group Representation, Isotropy Group, Lie Group Quotient Space, Matrix Group, Topological Group, Transitive
*This entry contributed by Todd
Rowland*

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## Cite this as:

Rowland, Todd. "Closed Subgroup." From *MathWorld*--A Wolfram Web Resource, created by Eric
W. Weisstein. https://mathworld.wolfram.com/ClosedSubgroup.html